A: Which one do you like better, going out or staying home?

B: I like outdoor activity better. Picnic and Mountain climbing are very good outdoor activities.

A: Could you tell me your reason?

B: First, the air is fresh outdoor and the scenery is beautiful. It is good for our health. Mountain climbing is a very good sport. These activities can tire us up(激发), get us refreshed（恢复精神） and released.

A: Well, it sounds interesting. But isn't it very demanding? You know I'm not that strong and I've never done that before.

B: Yeah, I think you should start training now.